High resolution melting: a useful field-deployable method to measure dhfr and dhps drug resistance in both highly and lowly endemic Plasmodium populations

Background: Emergence and spread of drug resistance to every anti-malarial used to date, creates an urgent need for development of sensitive, specifc and feld-deployable molecular tools for detection and surveillance of validated drug resistance markers. Such tools would allow early detection of mutations in resistance loci. The aim of this study was to compare common population signatures and drug resistance marker frequencies between two populations with diferent levels of malaria endemicity and history of anti-malarial drug use: Tanzania and Sénégal. This was accomplished by implementing a high resolution melting assay to study molecular markers of drug resistance as compared to polymerase chain reaction–restriction fragment length polymorphism (PCR/RFLP) methodology. Methods: Fifty blood samples were collected each from a lowly malaria endemic site (Sénégal), and a highly malaria endemic site (Tanzania) from patients presenting with uncomplicated Plasmodium falciparum malaria at clinic. Data representing the DHFR were derived using both PCR–RFLP and HRM assay; while genotyping data representing the DHPS were evaluated in Senegal and Tanzania using HRM. Msp genotyping analysis was used to characterize the multiplicity of infection in both countries. Results: A high prevalence of samples harbouring mutant DHFR alleles was observed in both population using both genotyping techniques. HRM was better able to detect mixed alleles compared to PCR/RFLP for DHFR codon 51 in Tanzania; and only HRM was able to detect mixed infections from Senegal. A high prevalence of mutant alleles in DHFR (codons 51, 59, 108) and DHPS (codon 437) were found among samples from Sénégal while no mutations were observed at DHPS codons 540 and 581, from both countries. Overall, the frequency of samples harbouring either a single DHFR mutation (S108N) or double mutation in DHFR (C59R/S108N) was greater in Sénégal compared to Tanzania Conclusion: Here the results demonstrate that HRM is a rapid, sensitive, and feld-deployable alternative technique to PCR–RFLP genotyping that is useful in populations harbouring more than one parasite genome (polygenomic infections). In this study, a high levels of resistance polymorphisms was observed in both dhfr and dhps, among samples from Tanzania and Sénégal. A routine monitoring by molecular markers can be a way to detect emergence of resistance involving a change in the treatment policy

Distribution of Parasites Detected in Stool Samples of Patients in Le Dantec University Hospital of Dakar, Senegal, from 2011 to 2015

To identify the parasites responsible for intestinal parasitic infections diagnosed at Le Dantec University Hospital of Dakar, distribution of parasites detected in stool samples of patients was studied. From 2011 to 2015, 2578 patients were included in the study. A direct examination and Ritchie technique were performed as parasite search techniques. In total, 408 samples were positive showing 440 intestinal parasites; this corresponds to prevalence of 15.8%. Parasites were detected in monoparasitism (85.7%) and multiparasitism (14.3%). The most common species found in monoparasitism were Entamoeba coli (38.9%), E. histolytica/dispar (12.7%), Giardia intestinalis (8%), and Ascaris lumbricoides (7.3%). The most common associations were A. lumbricoides-Trichuris trichiura (3.6%) and E. coli-G. intestinalis (2.7%). Nonhospitalized patients were significantly more affected with 65.4% compared to hospitalized counterparts; and also there were more men (50.7%) than women. With 67.4%, adults were the most affected age group, while the elderly were less affected with only 7% (p=0.5). This study shows increasing prevalence of intestinal parasitic infections over the years. So health education should be promoted in addition to the already begun mass treatment program. This would help to limit or even halt the spread of these diseases

Tinea pedis due to Cylindrocarpon lichenicola beginning onycholysis

A 33 year old woman presented with both feet, humid and white Tinea pedis at the second, third and fourth inter-toes areas associated with a beginning onycholysis of the nails lasting for 18 months. KOH mount of the samples was positive for fungal hyphae. The fungus was isolated on Sabouraud-chlorampphenicol agar and identified as Cylindrocarpon lichenicola. The patient was treated with an association of terbinafine tablet and terbinafine cream and presented clinical cure after three months